Nuts and bolts are essential fasteners used in construction and machinery. A bolt is a long metal rod with a head on one end and threads on the other, allowing it to be screwed into a nut. The nut is a small, hexagonal piece with a hole in the center that fits over the bolt's threaded end, securing two or more objects together. These fasteners come in various sizes and materials, such as steel, stainless steel, and plastic, to suit different applications. They are commonly used in everything from furniture assembly to automotive manufacturing, providing strength and stability to structures and devices.